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Chris Hill · 07-02-2007, 11:02 AM

If the cam is retarded 10 degrees, what happened to the ignition timing? If it's a distributor system, the ignition timing would have moved too, but I'm not sure if it would advance or reatard the ignition timing.

The "aluminum dust" sounds correct for detonation. It almost looks like sand. I'd also do a compression check and the "dust" running around can screw up valve sealing as well.

Another way to check detonation is to look at the bottoms of the pistons. I can't remember what they should look like, but it will different as more of the oil should have vaporized due to the increased temps. I read something by Smokey Yunick that spoke about that. Also, the rod and main bearings could be pretty hammerd out due to the detonation. That could be the loss of oil pressure.

07-02-2007, 11:02 AM	#2
Chris Hill Senior Member Join Date: Jan 2002 Posts: 655 Likes: 8 Liked 244 Times in 26 Posts	Re: Can Detonation Do This???? If the cam is retarded 10 degrees, what happened to the ignition timing? If it's a distributor system, the ignition timing would have moved too, but I'm not sure if it would advance or reatard the ignition timing. The "aluminum dust" sounds correct for detonation. It almost looks like sand. I'd also do a compression check and the "dust" running around can screw up valve sealing as well. Another way to check detonation is to look at the bottoms of the pistons. I can't remember what they should look like, but it will different as more of the oil should have vaporized due to the increased temps. I read something by Smokey Yunick that spoke about that. Also, the rod and main bearings could be pretty hammerd out due to the detonation. That could be the loss of oil pressure.